TR2/3/3A TR3, front suspension rebuild qustions

[IKE]

I'm restoring my 1960 TR3 and currently working on the front suspension. I bought some replacment parts a while back (a bushing replacment kit from Moss I think). When I started to replace bushings on the fulcrum and trunnion pins, the fit seems pretty sloppy. There does not appear to be any significant corrossion or wear on the pins. Could the replacment parts be out of spec? It just seems that the bushings in thsi area should fit pretty snug. I've read as much as I can find in the manual and some restoration books but still feel uninformed.

Are there specs for the pin sizes and clearances? I've got a pretty good shop and maybe it would be easier to make some parts myself. Maybe I need to get the bushing kits from a better vendor.

Any advice or places I should look for a walk thru? I'm kind of new at this so I feel pretty green.

Thanks

Ike

 

[TR3driver]

This question seems to be coming up a lot recently, so I went and measured some NORS parts I have on hand, that I believe to be correct.

The trunnion pins measure .6235" (give or take a few .0001") and the bushing is supposed to be reamed to .625", so the clearance here should be about .001".

The od of the inner steel sleeves reads .8125", id is .618".

I've got some nylon inner bushings to measure, but no time just now. I'll post that info later.

PS, Yes, replacement parts that don't fit properly is an unfortunately common problem; and No, I do not know of a written specification for these parts.

 

[PatGalvin]

Hello All
I'm a brand new member and this is my first post. I am currently cleaning 50 years of grease and grime and powdercoating suspension parts for a frame off 59 TR3A restoration. I've never rebuilt a suspension. Took lots of pics and notes during disassembly. I am using a TRF magic kit which seems pretty complete. Here's my question.

On the small (outer) end of the lower wishbone arms, there is a brass/bronze bushing that mates up to the lower trunion. How do I determine if these brass/bronze bushings need to be replaced? Do I simply fit up the new parts and give them a solid wiggle and check for play? Or should I find a competent machine shop and ask them to measure? I see Moss sells the new bushings and I'd have to pay someone to fit and ream them.

This car was pretty rusty when I bought it. I have some corrosion on the lower fulcrum pins. Because I am fitting new polished steel inserts and new nylon bushings, it seems like this corrosion is not a big deal. The polished steel inserts are certainly not pivoting on the lower fulcrum (frame) pins.

Any thoughts on this? Hope to have all parts clean and prep'd so I can reassemble next week.

Thanks for any help. I'll have lots more questions and the support is greatly appreciated.

Pat Galvin
Sacramento, CA

 

[PatGalvin]

Also, any need to fit grease fittings to the lower inner wishbone arms? I suppose you'd have to create a groove in the nylon for grease distribution as well as drill the nylon bushings so the grease would enter contact the polished pin that covers the lower trunions frame pins. Any thoughts or experience. If no grease fittings, then what assembly lube is appropriate for the nylon bushings and wishbone arms?

Pat Galvin
Sacramento, CA

 

[TR4nut]

Hi Pat & Welcome-

For checking the fit of the wishbone arms to the trunnions, basically all I did was the wiggle test - on my TR4 it was obvious that there was too much play. To refit, I used a fixed size 5/8" reamer which worked well on 3 of the 4 bushings but I rushed the last and had to redo. When I do it again on my 59 3A, I'm planning on a little slower operation with an adjustable set. Bushing replacement is doable on your own if you don't want to go the machine shop route - but you do need to invest in the reamer.

For the inner pins, yes I think the steel bushing can accomodate the corrosion on the inner pins - just put some anti-seize on there to help the next TR owner when another redo is needed.

Randy

 

[prb51]

the fit of the bushings should be snug, no wiggle side to side but should rotate if that makes sense to you.
If you have slop then either your trunnions are worn or the bushings are incorrect.
I replaced my trunnion bushings and you must ream them out with a 5/8th in reamer
https://www.use-enco.com/CGI/INSRIT?PMAKA=331-1140&PMPXNO=945503&PARTPG=INLMK32
if they rotate easily Pat, or have side to side wiggle they are toast.
The lower inner wishbone innards I lubed with an anti seize and no issues as there isn't that much movement (like the trunnions) and the uppers I occasionally spray with silicon lube as I have the silicone bushings as opposed to rubber.
I also used the TRF kit with sil bush upgrade.

 

[tdskip]

Welcome Pat! My in-laws are in Folsom, I'll send them over to help promptly.

Anti-seize is your friend.

Don't be shy about asking questions, and when you get a chance post a picture of two of your TR3.

 

[tinman58]

Welcome Pat!!
We are neighbors, just one hour away! Let's get that TR3 on the road!!

 

[TR3driver]

IMO, use grease, not anti-seize, when assembling the nylon inner bushings. Anti-seize has metal particles in it that will act as an abrasive. The book also notes that adding oil once in awhile is a good idea. AS is OK where the sleeves fit over the pins, though (since the sleeves are not supposed to move).

I converted to Nylatron bushings (mostly because the upper, rubber ones didn't seem to last very long); and added grease zerks to the arms. Also used a Dremel with a small ball burr to add grease channels, on the side away from the load. That was many years and miles ago; all but one of the Nylatron bushings got reused from the wrecked TR3A to the 'project' TR3.

My assumption is that, if the trunnion pins are worn at all, so are the bushings. I see that prb51 has already given you the link to a suitable reamer for much less than a shop will charge. IMO the fixed reamer works better than the cheap adjustable ones (and good adjustable ones are way too expensive).

(Couldn't find my 5/8" fixed the other day, so was reduced to using the adjustable ... not just a PITA but I ruined one of the bushings & had to redo it. It's a poor mechanic that blames his tools ... but it wouldn't have happened with a fixed reamer.)

 

[PatGalvin]

Hi Guys

Thanks much to you all for the quick replys. It is great to find other Triumph nuts so close to home. I greatly appreciate the help and will need much more in the future! The forum is a fantastic resource. I'll post some photos on PhotoBucket - the site is down for maintenance right now. Basically, the body is primed and stored at the blaster. The chassis is stripped, reinforced, and painted. And I've got the next few weeks to clean and build the front and rear suspension. Great fun!

Had one of these cars back in 1981 when I was graduating from LMU in Los Angeles. Sold it to leave for the Peace Corps. This is my new midlife crisis (cheaper than a Porsche or a Blonde!)

Pat

 

[mallard]

I second that, Have you seen the cost of rebuilding the front end of a blonde. Wecome to the forum Pat.

 

[tdskip]

IMO, use grease, not anti-seize, when assembling the nylon inner bushings.

I wasn't specific enough, I do use synthetic grease on the bushings to metal, but is anti-seize really bad for metal to metal?

 

[tdskip]

I second that, Have you seen the cost of rebuilding the front end of a blonde. Wecome to the forum Pat.

LOL!

 

[TR3driver]

but is anti-seize really bad for metal to metal?

Depends on whether the metal-to-metal joint normally moves or not. Anti-seize is great for joints that don't move during normal operation (eg bolt threads, exhaust pipe joints, wire wheels splines, and between the inner sleeves & pins). But it's not a lubricant for frequent motion.